Building a Simple Chatbot from Scratch in Python (using NLTK)

A chatbot is an artificial intelligence-powered piece of software in a device (Siri, Alexa, Google Assistant etc), application, website or other networks that try to gauge consumer's needs and then assist them to perform a particular task like a commercial transaction, hotel booking, form submission etc .Today almost every company has a chatbot deployed to engage with the users. The possibilities are (almost) limitless. There are broadly two variants of chatbots: Rule-Based and Self learning. The chatbot uses the message and context of conversation for selecting the best response from a predefined list of bot messages. The context can include a current position in the dialog tree, all previous messages in the conversation, previously saved variables (e.g.